Langerhans cell histiocytosis: A diagnostic challenge on thyroid fine needle aspiration cytology

Abstract

Thyroid gland involvement by Langerhans cell histiocytosis (LCH) is extremely rare. A 28‐year‐old woman with a history of polyuria, polydipsia and amenorrhoea presented with a diffuse thyroid swelling of 2 months duration. Clinical diagnosis was diabetes insipidus. Endocrine profile was normal. Fine needle aspiration cytology (FNAC) from thyroid revealed numerous large histiocytes with prominent nuclear grooves against an inflammatory background rich in eosinophils. A diagnosis of LCH was made and immunocytochemistry with CD1a confirmed the same. Subsequent skin biopsy also showed LCH. FNAC diagnosis of LCH in thyroid is challenging. The diagnostic pitfalls range from thyroiditis due to the presence of inflammatory cells in the background to papillary thyroid carcinoma due to grooved nuclei. Additional material should be collected at FNAC for ancillary studies to confirm the diagnosis.

Langerhans cell histiocytosis of thyroid and bilateral parotid diagnosed on fine needle aspiration cytology

“…LCH usually affects children and young adults, with the most common sites being bone, skin, lung, pituitary gland, and lymph nodes 3 . LCH involving the thyroid is a rare presentation, and fine needle aspiration cytology (FNAC) of this condition is infrequently documented in the literature 4,5 . Similarly, LCH involving parotid is a very rare condition 6 .…”

“…3 LCH involving the thyroid is a rare presentation, and fine needle aspiration cytology (FNAC) of this condition is infrequently documented in the literature. 4,5 Similarly, LCH involving parotid is a very rare condition. 6 LCH presenting as bilateral parotid swelling and synchronous involvement of the thyroid is not yet reported/documented in the literature.…”